Examples of cleaning apparatus for gas filters, such as baghouse filters cleaned by way of a reverse pulse jet, are disclosed in U.S. Pat. Nos. 5,421,845; 5,116,395; 4,878,926; 4,854,951, 4,655,799; 4,544,389; 4,539,025; 4,306,890; 4,293,320; 4,233,041; 4,157,899; 4,097,254; 4,022,595; 3,951,627; 3,832,832; 3,793,811; 3,695,007; 3,648,442; 3,543,481; 3,487,609; 3,482,378; 3,280,980; 3,277,633; and 2,974,748. The disclosures of these and all other publications referenced herein are incorporated by reference in their entirety for all purposes.